Use Of Subwoofers - Electro-Voice EVID Ceiling Speaker Systems Installation And Operation Manual

Appendix B — System Design Guide
tions that do not need the extended perform-
ance of the larger models.
Reverberant Rooms
and High Ceilings
Situations arise, however, in which con-
trolled coverage is more desirable than
broad dispersion. Very large live spaces
such as gymnasiums, convention centers,
shopping mall atriums, and the like all ben-
efit from more controlled sound projection.
In such installations, the EVID 8.2HC is the
best choice. Its 75-degree coverage pattern
above 1kHz provides more intelligibility in
large, acoustically live spaces. It also has a
high 93dB sensitivity rating for optimum
efficiency.
SPL Requirements: How Loud?
The EVID C8.2 is a great speaker to use
when higher SPL is required. The fidelity
and bandwidth of the unit is substantial and
is ideal for applications requiring high quali-
ty foreground music reproduction. The C8.2
has substantial low frequency energy down
below 60Hz. This is more than sufficient for
most applications.
Layout: How Many?
The chart below shows the effective cover-
age diameter of the EVID models assuming a
4-foot listening plane height. Using these fig-
ures you can lay out a coverage pattern for
the job after deciding the overlap criteria
described earlier on page 10.
Coverage Diameter by Ceiling Height
Model 8' 12'
C4.2 17' 34'
C8.2 11.5' 23'
C8.2HC 6.5' 12'
C10.1 180° coverage
EVID™ Ceiling Series Installation and Operation Manual
20' 24'
68' 85'
45' 57'
24' 30'

Use of Subwoofers

The C10.1 subwoofer can add considerable
low-frequency performance to any EVID
installation. It is important to note that the
C10.1 subwoofer depends on the ceiling
and walls to properly load itself and to rein-
force its bass output. Correct positioning is
important to get maximum impact.
In smaller rooms when a single C10.1 is
used, a center or near-center position is
best. This gives the most even coverage. For
larger rooms where more than one C10.1
are employed, the added effect of the
room's walls can be used. In such a space,
position the subwoofers evenly throughout
the room and a few feet from the wall or
corners. The added loading of the walls will
enhance the response in these larger areas.
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